(n.) The process of reasoning, or deducing conclusions from premises; deductive reasoning.

abstract thought act of thought brainwork cerebration cogitation conceit conception conceptualization conclusion creative thought deduction deductive reasoning demonstration discourse discourse of reason discursive reason excogitation headwork heavy thinking idea ideation illation imageless thought induction inductive reasoning intellection intellectual exercise intellectualization judgment logical thought mental act mental labor mental process mentation noesis philosophy proof rationalism rationality rationalization rationalizing reason reasonableness reasoning sequitur sophistry specious reasoning straight thinking sweet reason thinking thinking aloud thinking out thought